This invention relates to boat hulls generally, and more particularly to an improved planing-type hull for providing substantially improved stability and maneuverability in rough water.
Planing-type hulls are designed to move generally over the water rather than through it, as do displacement type hulls. Planing can be defined as that stage at which dynamic forces due to the motion of the hull through the water begin to make their influence felt.
May previously issued U.S. Pat. No. 3,996,869 disclosed and claimed a dihedral tunnel boat hull having side floats coextensive with a substantially V-shaped central hull. As disclosed in that patent, deep V hulls provide the softest riding hull in rough or choppy water. My earlier patented design was successful in overcoming many of the drawbacks of a deep V hull, primarily instability, through the use of a central V hull with side floats. These side floats had deeper drafts than the central hull. Once the desired speed is reached, the outer floats approach the desired planing motion. These side floats had outer hull surfaces which were stepped, while the inner surfaces were substantially vertical. A draft angle minimum of 3.degree. is essential to withdraw a manufactured part from a mold. My earlier design was successful in providing a softer, smoother ride over rough water at speeds in excess of 30 m.p.h., as well as providing greater load carrying capabilities.
However, my earlier dihedral boat hull did not achieve the degree of maneuverability in rough water that a true planing-type hull would have in smooth water. While maintaining substantial portions of the basic design as disclosed in my previously issued U.S. Pat. No. 3,996,869, additional changes were required to achieve the degree of stability and maneuverability possible with this improved bihedral tunnel boat hull design.